I am under water according to my very accurate SCX-20
- Thread starter backman
- Start date
Quitsa
Furuno Super Fan
Go to the sensor menu under initial settings and enter the SCX-20 setup mode and check the antenna position settings. There is one for the height of the unit.
If that is correct, it is possible that there are one or more low satellites that are poor fixes contributing to an error. You could try changing the "SV" value in the GNSS setup menu to raise the minimum elevation of satellites that are used to determine position.
You might also try turning off the Galileo and GLONASS and see what impact that has on the position fix.
Or you could do what I do, which is ignore the altitude readings since the position values are consistently super accurate and show me dead center in the pilings in my slip and running down the middle of the narrow channel between those rather unforgiving stone jetties that you know pretty well. I have a feeling that marine GPS systems are not designed to ensure accurate altitude measurements since I have seen altitude errors with every one I have ever had.
If that is correct, it is possible that there are one or more low satellites that are poor fixes contributing to an error. You could try changing the "SV" value in the GNSS setup menu to raise the minimum elevation of satellites that are used to determine position.
You might also try turning off the Galileo and GLONASS and see what impact that has on the position fix.
Or you could do what I do, which is ignore the altitude readings since the position values are consistently super accurate and show me dead center in the pilings in my slip and running down the middle of the narrow channel between those rather unforgiving stone jetties that you know pretty well. I have a feeling that marine GPS systems are not designed to ensure accurate altitude measurements since I have seen altitude errors with every one I have ever had.
wkearney99
Furuno Super Fan
Also understand that the earth is not perfectly round (it's an oblate sphere). GPS does not necessarily resolve to the "actual" surface. That and I'm guessing tides come into play as well. There's plenty of very deep rabbit holes you can go down understanding GPS, geoids, ellipsoids and various fudge-factors that come into play for all this.
As 'Quitsa' points out, ignore altitude is probably your best bet. It's not like you need it for marine navigation.
As 'Quitsa' points out, ignore altitude is probably your best bet. It's not like you need it for marine navigation.
The sky is falling!! Boats are not airplanes and the infomation doesn't mean what one might think. Please see the topic already discussed.
https://www.furunousaforum.com/viewtopi ... 04&p=27623
https://www.furunousaforum.com/viewtopi ... 04&p=27623
Similar threads
